Payero, 22, is preparing to represent Argentina at the Tokyo Olympics and is then set to fly to the North East to join up with the Boro squad.
Supporters will be keen to see Payero in action and wondering where he’ll fit into the side as the Teessiders aim to challenge for promotion.
Argentine journalist German Garcia Grova told the Mail that Payero is a ‘box-to-box midfielder who has a great long shot, great vision and he can also dribble with the ball.’
Warnock has spoken with Payero and says the playmaker can operate as a No 8 or a No 10, which should help bolster the side’s attacking options.
The Boro boss remains hopeful he can make more signings this summer, but here’s what the current side could look like with Payero involved.
1. GK: Joe Lumley
Will expect to be Boro's No 1 goalkeeper this season after arriving on a free transfer from QPR. Photo: Getty Images
2. RB: Anfernee Dijksteel
Missed the end of last season with an ankle injury but the 24-year-old is set to play a big part this campaign. The Dutchman's composure on the ball and ability to read the game will be a big asset regardless of the system. Photo: George Wood
3. Dael Fry
Warnock believes the 23-year-old centre-back is the best in the Championship. The Boro boss will hope Fry can stay fit and be a mainstay in defence. Photo: Getty Images
4. CB: Grant Hall
Could be the perfect partner for Fry and the pair played well alongside each other last season. Hall, 29, missed the first half of last season through injury but was a commanding figure when he returned to the side. Photo: Stu Forster